Clot-Busting Drugs: One Size Doesn't Fit All

May 15, 2000 -- Clot-busting drugs, which are currently used as the best emergency treatment for heart attack patients, don't help patients over age 75 and may actually do harm. This is in dramatic contrast to the experience of patients younger than 75. In the younger group, for every 100 patients treated with clot busters, one life is saved.

"We confirmed in this very large, nationwide study that patients younger than 75 years clearly do benefit from these drugs," says senior author Neil R. Powe, MD, MPH, MBA. "However, our study raises concerns that thrombolytic [clot-busting] therapy may not offer any benefit to older patients, and, in fact, may do harm." Powe is professor of medicine, epidemiology, health policy, and management at the Johns Hopkins University School of Medicine in Baltimore.

The study, by a research team at Johns Hopkins University, looked at almost 8,000 Medicare patients aged 65 to 86 years who had heart attacks. Those under 75 receiving clot busters had a 6.8% death rate 30 days after the heart attack. Nearly 10% of these patients died when they did not get the drugs. But in the older patient group, those getting clot busters were 40% more likely to die within 30 days of treatment.

While the research team did not gather data on causes for the increased death rate, Powe speculates it may be due to medication side effects, such as excessive bleeding or heart beat disturbances.

"This study offers an interesting analysis of what has happened over the course of several years in patients" receiving clot-busting drugs, says Thomas Davis, MD. "It has found what many of us in active practice believed to be the case: that older patients may not do as well" on these drugs. Davis is the medical director of the cardiac intensive care unit at St. John Hospital in Detroit.

He believes physicians should take the results of this study very seriously, particularly since now there are other options available for emergency treatment. Sophisticated hospitals may be able to do an angioplasty, in which a tiny balloon is used to open the blocked vessel in the heart. "In a facility that doesn't offer angioplasty, [the physician should] consider using other new medications," Davis says. "These medications could serve to stabilize the patient for transfer to an institution that can do angioplasty."